Adjuvant trastuzumab in the treatment of small HER2-positive tumors: A single institu
 

Adjuvant trastuzumab in the treatment of small HER2-positive tumors: A single institution experience.

Abstract No:
e11514
Publication-only abstracts (abstract number preceded by an "e"), published in conjunction with the 2014 ASCO Annual Meeting but not presented at the Meeting, can be found online only.

Author(s): Maria Vita Sanò, Eleonora Taibi, Marco Ali, Rosanna Di Marco, Alessandra Zacchia, Maurizio Chiarenza, Giuseppina Fallica, Silvia Clementi, Rosa Anna Aiello, Michele Caruso; Medical oncology Department, Humanitas Centro Catanese di Oncologia, Catania, Italy; Humanitas Centro Catenese di Oncologia, Catania, Italy; Humanitas Centro Catanese di Oncologia, Catania, Italy
Abstract Disclosures

Abstract:

Background: According to St.Gallen Criteria, a high risk node-negative patients will be defined as a patients with negative lymph node involvement and at least one of following factors:tumor size > 2 cm, HR negative, histological and/or nuclear grade 2-3 or age < 35 years.However some patients with HER2 positive cancers develop a recurrence despite small tumor size (< 2 cm) and none of these factors. Six phase III multi-centre trials confirmed the potential benefit of incorporating trastuzumab in adjuvant regimens as a standard treatment. The effectiveness of adjuvant trastuzumab has been demonstrated either for node negative pT1c patients and for diseases at a higher risk. These trial were not able to provide any information regarding the outcome of patients with node negative tumours <1cm. Methods: From Jannuary 2005 to November 2013 in our istitution 101 patients with small Her2 positive and negative nodes breast cancers underwent surgery. 83/101(82,2%) patients had quadrantectomy and local radiotherapy, 18/101( 17,8 %) patients had radical mastectomy. Median age at diagnosis was 50,3 years (range 27- 76). All patients were staged as pT1 N0 M0 : 9/101(8,9 %) patients are pT1a N0, 21/101 (20,8 %) patients pT1b pN0 and 72/101 (71,2 %) patients pT1c pN0. 96/101 (95 %) patients were treated with adjuvant anthracyclines regimens for 4 or 6 cycles followed by one year of trastuzumab ( 52 weeks).70/101 patients follow-up was at least 1 year, median follow up was 46 months ( range 13 months – 108 months). The Left Ejection Ventricular Fraction (LEVF) was assessed at baseline and every three months. Results: 2/70 (1.4%) patients relapsed (one lung metastasis during treatment, one local recurrence 13 months after the last dose). An asymptomatic absolute decrease in LVEF by 10% was reported in five patients. No patients discontinued the treatment. Conclusions: The use of trastuzumab in HER2 positive small tumor seems safe and effective. More data should be available for tumors smaller than 1 cm.